A steel casting process uses the solidification of steel to form the rough shape of the final product. The liquid steel is poured into a prepared mold of the desired shape. The mold is normally made of silica sand held to shape by the use of a binder such as clay-water or a chemical reaction binder. The liquid metal is poured into an opening in the body of the mold and through a channel to the actual mold cavity. The channel system or the path in which the liquid metal flows to the mold cavity is called a gating system. In general, the liquid metal is poured from a holding vessel, normally loaded through the air into the gating system and into the mold easting cavity.
A major difficulty encountered in steel casting production is that metallic oxide particles are trapped in the steel product; said particles being called inclusions. These particles trapped in the product can cause difficulty in further processing of the casting such as machining and/or cause poor service performance. The inclusions, metallic oxide particles, can form because of a chemical reaction of the liquid metal with a source of oxygen such as air or because of physical entrapment of existing oxides by the liquid metal flow. Our gating system is designed to resist the erosive force of liquid metal flow and to trap the metallic oxide particles before the liquid metal enters the casting cavity.
Our improved gating system design combines floatation, centrifugal force and metal-inclusion-refractory surface chemistry to remove or trap metallic oxide inclusions prior to the introduction of metal into the casting mold cavity.